Submitted material showing subepithelial sheets of diffuse population of large round cells with vesicular nuclei and active mitosis. Main possibility is diffuse large cell non-Hodgkin's lymphoma. For confirmation of this diagnosis and definitive exclusion of undifferentiated carcinoma, marker study (CK, LCA and CD20) is needed.
Nasopharyngial mass.
Soft tissue fragments measuring in aggregate 4 x 3.5 x 1 cm, totally embedded.
Nasopharyngeal mass, biopsy: